Cells were crosslinked with 1% methanol-free formaldehyde (ThermoFisher) for 7-10 min at room temperature, followed by quenching with 100 mM Tris pH8.0 and 25 mM Glycine, and the cells were lysed in SDS buffer. Cytoplasm was lysed using 50 mM Tris-HCl pH 8.0, 100 mM NaCl, 5 mM EDTA, 1% SDS for 10 min and nuclei were precipitated by centrifugation at 10,000´g. Nuclei were resuspended in 66 mM Tris-HCl pH 8.0, 100 mM NaCl, 5 mM EDTA, 1.7% Triton X-100, 0.5% SDS and sheared using E100S (Covaris) to chromatin fragments of 200-400 base-pair DNA size. 1-10 ng of DNA was used in preparation of Illumina-compatible libraries using ThruPlex DNA kit (Rubicon Genomics) Illumina Next Gen Sequencing NextSeq platform (Illumina, San Diego, CA) was used to obtain 1-5´107 unique sequencing paired-end tags